RWS, the thought to try the mag drill for an inspection hole sure turned out lucky.
Those different series of numbers on the recipe cards were the numbers dialed to zero in on the final combination. Since the borescope was looking inside the change key hole you could see the lock’s wheels and their gates and the change key openings on each wheel. The first visible wheel is the 1st no.
To line up all the change key holes in the view of the borescope you have to first dial the 1st no. in the proper direction (CCW) then look for the 2nd no. while dialing CW without disturbing the 1st no. Then look for the 3rd no. by dialing CCW without disturbing either of the previous two numbers.
Once we had all the change key holes in view, it took some tweaking of those numbers to correct for the offset view of the borescope and getting the exact numbers for everything to be in perfect alignment. It’s not difficult, but you have to concentrate and think about which number and the direction you want to tweak it by dialing the correct way to move it. Keeping in mind that to change no. 1, you then have to redial nos. 2 &3. To change #2, you’d have to also redial #3. Once we had the proper combination dialed, turning the dial CW to the stop should allow for the handle to retract the bolts on the door.
Knowing where to drill: Without any clue as to how the lock was mounted inside, the best choice was then to drill the hole as close to inline with the dials center. We didn’t have a clue as to what we’d be able to see. But we could move the borescope around to have a look if we needed to somehow unscrew a cover through that inspection hole. As luck would have it, we spotted the hole in the mechanisms cover plate to allow access to the lock’s change key hole only a couple inches off center from our inspection hole. Not needing to remove a cover plate and finding visible access to the change key hole was pure luck.
I hate to give you another reason to spend more money......but for much less than a commercial duty mag drill.... this one sure seems to work great:
Magnetic Drill: A friend who has this same drill recommended it to me. He’s had his for years and said for home use projects it works great. A Vevor model 8860. I found it on sale for just under $200. Variable speed and up to 2 inch capacity. With the annular cutters I purchased, the drill had no issue walking right through that 1 inch thick steel wall. I was impressed!! A minor drawback for me is there is no reverse.
(Note: I have the drills spoke handles removed so that it can just barely fit in my tool cabinet until I find a better spot for it.)
